SIBO testing

Question 1

Small intestinal bacterial overgrowth (SIBO)

Answer 1

Small intestinal bacterial overgrowth (SIBO) = a bacterial count in the small intestine of over 105 CFU / ml.

• In SIBO, fermentation of carbohydrates in the small intestine results in raised hydrogen or methane.
• Breath-testing is a non-invasive test that is looking for the gases made by fermenting bacteria (hydrogen or methane) after set points in time in which the patient has ingested a substrate that the bacteria eats.
• After the substrate is taken, breath samples are collected every 20 or 30 minutes

Question 2

Substrates

Answer 2

‒ Lactulose (very popular — may give false positives as it is known to speed up transit time, making it hard to read).

‒ Glucose (there are less false positives, but absorbs quickly so might not pick up distal positives).

‒ Fructose (less commonly used; gives you the bonus of seeing if there is fructose intolerance)

Question 3

SIBO testing

Answer 3

• Breath test substrates — rely on your case taking to see what types of foods to which your client reacts worst out of the three substrates, to get an idea of the best substrate to use.
• Consider doing a SIBO test alongside a stool test as it is rarely present in isolation, it is a part of a bigger ecosystem disorder.

Question 4

Breath test preparation diet

Answer 4

• A strict preparation diet should be done 24 hours before to get an accurate baseline, where microbiota-feeding foods need avoiding.
• The only foods allowed are:

– Any meat / poultry / fish / seafood that is not cured or brined.
– Plain, steamed white rice (not brown).
– Eggs.
– Clear meat broth (made only from the meat, no bone / cartilage or vegetables).
– Fats / oils (coconut / olive / vegetable oils, butter, or lard).
– Salt and pepper (no other herbs / spices)

Question 5

Gases analysed:

Increase in hydrogen

Answer 5

• A rise of 20 ppm before 90 minutes

Question 6

Gases analysed:

Increase in methane

Answer 6

• A rise of 12 ppm before 90 minutes (or in severe constipation, a rise as little as 3 ppm might indicate a problem).

Question 7

Gases analysed:

Increase in combined methane / hydrogen:

Answer 7

• A combined rise of 15 ppm before 90 minutes.
• When fructose is used as the substrate, fructose intolerance can also be determined by a rise of gas in the large intestine after 120 minutes